[TOC]
- 封裝
- 繼承
- 多型
- 抽象
Duck 鴨子行為範例
behavior盡量以HAS-A(有一個)，而不是用繼承
Strategy Pattern 策略模式
classDiagram
Duck *.. FlyBehavior
Duck *.. QuackBehavior
class Duck {
<<abstract>>
#QuackBehavior quackBehavior
#FlyBehavior flyBehavior
+performFly()
+performQuack()
}
QuackBehavior <|.. MuteQuack
class QuackBehavior {
<<interface>>
+quack()
}
class MuteQuack {
+quack()
}
FlyBehavior <|.. FlyWithWings
FlyBehavior <|.. FlyNoWay
class FlyBehavior {
<<interface>>
+fly()
}
class FlyWithWings {
+fly()
}
class FlyNoWay {
+fly()
}
Weather 天氣觀測站範例
classDiagram
Subject <|.. WeatherData
class Subject {
<<interface>>
+registerObserver(Observer observer)*
+removeObserver()*
+notifyObserver()*
}
class WeatherData {
-List~Observer~ observers
-float temperature
-float humidity
-float pressure
+registerObserver(Observer observer)
+removeObserver()
+notifyObserver()
}
DisplayElement <|.. CurrentConditionDisplay
Observer <|.. CurrentConditionDisplay
Subject ..* CurrentConditionDisplay
class DisplayElement {
<<interface>>
+display()
}
class Observer {
<<interface>>
+update(float temp, float humidity, float pressure)
}
class CurrentConditionDisplay {
-float temperature
-float humidity
-float pressure
-Subject weatherData
+CurrentConditionDisplay(WeatherData weatherData)
+display()
+update(float temp, float humidity, float pressure)
}
Beverage 飲料販賣範例
classDiagram
Beverage <|-- CondimentDecorator
Beverage <|-- Espresso
Beverage <|-- DarkRoast
class Beverage {
<<abstract>>
#String description
+cost()* double
+getDescription() String
}
class Espresso {
cost() double
}
class DarkRoast {
cost() double
}
CondimentDecorator <|-- Mocha
CondimentDecorator <|-- Whip
class CondimentDecorator {
<<abstract>>
+getDescription()* String
}
class Mocha {
-Beverage beverage
+Mocha(Beverage beverage)
+cost() double
}
class Whip {
-Beverage beverage
+Mocha(Beverage beverage)
+cost() double
}
於抽象類別定義抽象方法，將實際運作的方式交給次類別實踐
classDiagram
NYStylePizza --o NYStylePizzaStore
class NYStylePizzaStore {
createPizza() Pizza
}
Pizza <|-- NYStylePizza
class Pizza {
<<abstract>>
}
class NYStylePizza
PizzaStore <|-- NYStylePizzaStore
class PizzaStore {
<<abstract>>
+orderPizza() Pizza
#createPizza()* Pizza
}
建立介面、方法回傳的值也皆為介面，由實作物件去實踐這些方法、回傳的實際物件
classDiagram
PizzaIngredientFactory <|.. NYPizzaIngredientFactory
NYPizzaIngredientFactory --> ThinCrustDough
NYPizzaIngredientFactory --> MarinaraSauce
class PizzaIngredientFactory {
<<interface>>
+createDough()* Dough
+createSauce()* Sauce
}
class NYPizzaIngredientFactory {
+createDough() Dough
+createSauce() Sauce
}
Dough <|.. ThinCrustDough
class Dough {
<<interface>>
}
class ThinCrustDough
Sauce <|.. MarinaraSauce
class Sauce {
<<interface>>
}
class MarinaraSauce
Pizza <|-- ClamPizza
class Pizza {
<<abstract>>
String name;
Dough dough;
Sauce sauce;
#prepare()*
bake()
cut()
box()
setName(String name)
getName() String
}
class ClamPizza {
PizzaIngredientFactory ingredientFactory
+ClamPizza(PizzaIngredientFactory ingredientFactory)
prepare()
}
ClamPizza --* NYPizzaStore
Pizza --* PizzaStore
PizzaStore <|-- NYPizzaStore
NYPizzaStore --> Sauce
NYPizzaStore --> Dough
NYPizzaStore --> PizzaIngredientFactory
class PizzaStore {
<<abstract>>
+orderPizza(String type) Pizza
#createPizza(String type)* Pizza
}
class NYPizzaStore {
#createPizza(String type)
}
sequenceDiagram
participant customer as 客戶
participant pizzaStore as 披薩店
participant ingredientFactory as 原物料工廠
customer ->>+ pizzaStore: order pizza
loop
pizzaStore ->>+ ingredientFactory: get ingredient(Dough,Sauce...)
ingredientFactory ->>- pizzaStore: give ingredient
end
pizzaStore ->>- customer: give pizza
只能有一個實例
將請求封裝為物件
classDiagram
SimpleRemoteControl --> Command
SimpleRemoteControl --> Light
Command <|.. LightOnCommand
class Command {
<<interface>>
+execute()* void
+undo()* void
}
class Light {
+on() void
+off() void
}
class LightOnCommand {
Light light
+LightOnCommand(Light light)
+execute()
}
class SimpleRemoteControl {
-Command slot
+setCommand(Command command) void
+buttonWasPressed() void
}
將一個介面轉成另一個介面
classDiagram
Target <|.. Adapter
Adapter --> Adaptee
class Target {
<<interface>>
request()* void
}
class Adapter {
request() void
}
class Adaptee {
specificRequest()
}
讓介面更簡化